1. Field of the Invention
The invention relates to a method for monitoring an electromotively driven fuel pump of a fuel feed unit for a motor vehicle, in which a pump control apparatus supplies the fuel pump with electrical current and to a fuel feed unit for a motor vehicle having an electromotively driven fuel pump and having a pump control apparatus for activating the fuel pump.
2. Description of the Related Art
In fuel feed units, there is a risk that the fuel pump does not receive any fuel and may therefore run dry, or that fuel escapes into the environment in the event of a leak. Because of a failure of lubrication dry running of the fuel pump leads to rapid wear and failure of the fuel pump. Leakage outside a fuel tank receiving the fuel pump pollutes and endangers the environment.
The fuel feed unit could be monitored by a pressure sensor and the risks mentioned could be detected, since the pressure generated by the fuel pump falls drastically in the event of dry running or leakage. However, such a pressure sensor entails a high outlay in structural terms. Moreover, in the most unfavorable case, the pressure sensor itself is a fault source.